Speaker device capable of restraining polarization, method for adjusting diaphragm balance position, and method for adjusting diaphragm compliance performance

Abstract

The present invention discloses a speaker device capable of restraining polarization, a method for adjusting a diaphragm balance position of the speaker device and a method for adjusting diaphragm compliance performance of the speaker device. The speaker device comprises a vibration system, a magnetic circuit system, a shell accommodating the vibration system and the magnetic circuit system, a first electret layer, a second electret layer and a third electret layer, wherein the first electret layer, the second electret layer and the third electret layer have the same electric charge polarity; the first electret layer is attached to the vibration system; the second electret layer is attached to a first fixing component above the vibration system and opposite to the first electret layer; the third electret layer is attached to a second fixing component below the vibration system and opposite to the first electret layer; and the first electret layer, the second electret layer and the third electret layer are parallel to one another. In the present invention, an electrostatic field force is adopted to restrain the polarization of a diaphragm in a vibration direction.

The invention claimed is: 
     
       1. A speaker device capable of restraining polarization, comprising:
 a vibration system, a magnetic circuit system, a shell accommodating the vibration system and the magnetic circuit system, a first electret layer, a second electret layer and a third electret layer, wherein the first electret layer, the second electret layer and the third electret layer have the same electric charge polarity; 
 the first electret layer is attached to the vibration system; the second electret layer is attached to a first fixing component above the vibration system and opposite to the first electret layer; the third electret layer is attached to a second fixing component below the vibration system and opposite to the first electret layer; and the first electret layer, the second electret layer and the third electret layer are parallel to one another; 
 the vibration system comprises a diaphragm and a voice coil located below the diaphragm, and the first electret layer is attached to the diaphragm; and 
 a first thermal resistance material layer is arranged between the diaphragm and the voice coil and configured to isolate the first electret layer from the voice coil. 
 
     
     
       2. The device of  claim 1 , wherein the first thermal resistance material layer covers the whole area of the diaphragm, or is arranged only at an area where the diaphragm is connected to the voice coil. 
     
     
       3. The device of  claim 1 , wherein the diaphragm comprises a diaphragm body part and a reinforcing part; the diaphragm body part includes a plane part located in the middle and a surround part located at the edge of the plane part; the reinforcing part is arranged above the plane part; and the first electret layer is arranged at the side, close to the voice coil, of the plane part, or is arranged at the side, close to the reinforcing part, of the plane part, or is arranged above the reinforcing part. 
     
     
       4. The device of  claim 3 , wherein the first thermal resistance material layer covers the whole area of the diaphragm body part, or only covers the whole area of the plane part, or is arranged only at the area where the diaphragm is connected to the voice coil. 
     
     
       5. The device of  claim 1 , wherein each of the first electret layer, the second electret layer and the third electret layer is provided with the same number of independent areas; all of the independent areas have the same shape and size; all of the independent areas of the first electret layer are equal in electric charge quantity and are symmetrically distributed with respect to a center point of the diaphragm; all of the independent areas of the second electret layer are equal in electric charge quantity and are in one-to-one correspondence with the independent areas of the first electret layer; and all of the independent areas of the third electret layer are equal in electric charge quantity and are in one-to-one correspondence with the independent areas of the first electret layer. 
     
     
       6. The device of  claim 5 , wherein the diaphragm comprises a diaphragm body part and a reinforcing part connected with the diaphragm body part; and all of the independent areas of the first electret layer are distributed at the edge of a connection area of the diaphragm body part and the reinforcing part. 
     
     
       7. The device of  claim 1 , wherein the shell comprises a front cover arranged above the vibration system; and the second electret layer is attached to the front cover and arranged at the side, facing the vibration system, of the front cover. 
     
     
       8. The device of  claim 1 , wherein the vibration system comprises a diaphragm and a voice coil located below the diaphragm; the magnetic circuit system is located below the vibration system, and comprises a washer; and the third electret layer is attached to the washer and arranged to the side, close to the diaphragm, of the washer. 
     
     
       9. The device of  claim 8 , further comprising a second thermal resistance material layer arranged between the third electret layer and the washer. 
     
     
       10. The device of  claim 1 , wherein the first electret layer, the second electret layer and the third electret layer are electret thin films or electret plates. 
     
     
       11. The device of  claim 1 , wherein the thicknesses of the first, second and third electret layers are in the scale of μm-mm. 
     
     
       12. The device of  claim 1 , wherein a material of the first electret layer, the second electret layer and the third electret layer comprises any one or a combination of a fluorinated ethylene propylene copolymer, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyetherimide, polyethylene terephthalate, expanded polytetrafluoroethylene, and polyvinylidene difluoride. 
     
     
       13. A method for adjusting a diaphragm balance position of a speaker device, the method comprising the following steps:
 providing a speaker device capable of restraining polarization, comprising:
 a vibration system, a magnetic circuit system, a shell accommodating the vibration system and the magnetic circuit system, a first electret layer, a second electret layer and a third electret layer, wherein the first electret layer, the second electret layer and the third electret layer have the same electric charge polarity; 
 the first electret layer is attached to the vibration system; the second electret layer is attached to a first fixing component above the vibration system and opposite to the first electret layer; the third electret layer is attached to a second fixing component below the vibration system and opposite to the first electret layer; and the first electret layer, the second electret layer and the third electret layer are parallel to one another; and 
 the vibration system comprises a diaphragm and a voice coil located below the diaphragm, and the first electret layer is attached to the diaphragm; and 
 
 adjusting a ratio of an electric charge quantity Q 2  carried by the second electret layer to an electric charge quantity Q 3  carried by the third electret layer according to a formula 
 
       
         
           
             
               
                 
                   
                     Q 
                     2 
                   
                   
                     Q 
                     3 
                   
                 
                 = 
                 
                   
                     d 
                     1 
                     2 
                   
                   
                     d 
                     2 
                     2 
                   
                 
               
               , 
             
           
         
          so as to adjust the balance position of the diaphragm, wherein a distance between the first electret layer and the second electret layer is d 1 , and a distance between the first electret layer and the third electret layer is d 2 . 
       
     
     
       14. A method for adjusting diaphragm compliance performance of a speaker device, the method comprising the following steps:
 providing a speaker device capable of restraining polarization, comprising:
 a vibration system, a magnetic circuit system, a shell accommodating the vibration system and the magnetic circuit system, a first electret layer, a second electret layer and a third electret layer, wherein the first electret layer, the second electret layer and the third electret layer have the same electric charge polarity; 
 the first electret layer is attached to the vibration system; the second electret layer is attached to a first fixing component above the vibration system and opposite to the first electret layer; the third electret layer is attached to a second fixing component below the vibration system and opposite to the first electret layer; and the first electret layer, the second electret layer and the third electret layer are parallel to one another; and 
 the vibration system comprises a diaphragm and a voice coil located below the diaphragm, and the first electret layer is attached to the diaphragm; and 
 
 adjusting an electric charge quantity Q 1  carried by the first electret layer, an electric charge quantity Q 2  carried by the second electret layer and an electric charge quantity Q 3  carried by the third electret layer, so as to adjust the compliance performance of the diaphragm.